SAMPLED

MIDI, formats and standards · updated 2026-08-16

BUFFER UNDERRUN / DROPOUT

The CPU misses its deadline and the audio device plays empty samples, heard as a click or gap. Larger buffers and fewer live plugins fix it.

MIDI DIN in/out connectors on an RME audio interface card — the physical ports behind the MIDI, interface and I/O terms in this section.
MIDI, formats and standards — MIDI DIN in/out connectors on an RME audio interface card — the physical ports behind the MIDI, interface and I/O terms in this section.

Photo: RME Hammerfall DSP 9652 MIDI connectors (opens in a new tab) by Dan Lynch (opens in a new tab), via Wikimedia Commons — CC BY-SA 2.0 (opens in a new tab)

Key takeaways

  • The CPU misses its deadline and the audio device plays empty samples, heard as a click or gap.
  • Larger buffers and fewer live plugins fix it.
  • Causes include CPU spikes, disk throughput, aggressive power management and background processes.
  • Freezing or bouncing heavy virtual instruments is usually a faster fix than raising the buffer size again.
  • Watch out: only ever raising the buffer.

Quick checklist

  • Can you define buffer underrun / dropout in one sentence without looking?
  • Can you point at buffer underrun / dropout in a real session, mix or contract?
  • Have you tried the practical move above at least once?
  • Would you catch the common mistake before it costs you a take?
  • Have you opened one of the primary sources below rather than a forum thread?

BUFFER UNDERRUN / DROPOUT IN DEPTH

A dropout occurs when the audio engine cannot fill the next buffer in time, producing a click, a stutter or a stopped transport. Causes include CPU spikes, disk throughput, aggressive power management and background processes.

How it works in practice

Freezing or bouncing heavy virtual instruments is usually a faster fix than raising the buffer size again.

The mistake people make

Only ever raising the buffer. If the cause is disk streaming or a power profile, latency goes up and the dropouts stay.

WHERE BUFFER UNDERRUN / DROPOUT SITS

Buffer underrun / dropout belongs to midi, formats and standards in the Sampled music glossary. The plumbing — the specs your gear, files and delivery pipeline agree on.

TEST YOURSELF

0/3 answered · 0 correct

3 quick questions on buffer underrun / dropout. Answers are marked instantly — nothing is sent anywhere.

  1. 1. Which statement best describes buffer underrun / dropout?

  2. 2. What is the mistake people most often make with buffer underrun / dropout?

  3. 3. In practice, which of these applies to buffer underrun / dropout?

Ready for the full thing? Take the 25-question terminology test and get a certificate with your name and score.

SOURCES AND CITATIONS

Free, primary references for buffer underrun / dropout — standards bodies, manufacturers, government offices and university course material. Each one lists the line of this entry it backs up.

  • Apple — Logic Pro User Guide (opens in a new tab)

    Primary reference · support.apple.com

    “The CPU misses its deadline and the audio device plays empty samples, heard as a click or gap.”— the claim this source supports

    Why it counts: Published by the organisation responsible for the thing being defined, so it is a first-hand source rather than a summary of one.

  • Steinberg developer resources (opens in a new tab)

    Primary reference · steinberg.net

    “Larger buffers and fewer live plugins fix it.”— the claim this source supports

    Why it counts: Published by the organisation responsible for the thing being defined, so it is a first-hand source rather than a summary of one.

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